1510

Extend the curb no farther than the width of the parking lane. (See Chapter 1140 for shoulder width guidance.) Consider an approach nose and low-level landscaping that does not create a sight obstruction. At intersections with traffic signals, the curb extensions can be used to reduce pedestrian signal timing. Examples of sidewalk curb extensions are shown in Exhibits 1510-19 and 1510-20.

Improved Line of Sight at Intersection

Exhibit 1510-19

Curb Extension Examples

Exhibit 1510-20

The right-turn path of the design vehicle is a critical element in determining the size and shape of the curb extension. Sidewalk curb extensions tend to restrict the width of the roadway and can make right turns difficult for large trucks. Ensure the geometry of the curb extension is compatible with the turn path for the design vehicle selected.

Avoid interrupting bicycle traffic with curb extensions.

Do not use curb extensions on state highways when:

The design vehicle (see Chapter 1310) encroaches on curbs, opposing lanes, or same-direction lanes, and mountable curbs or other solutions will not improve the circumstances.

On-street parking is not provided/allowed.

The posted speed is above 35 mph.

Plantings that do not obstruct the vision of pedestrians or drivers may be used within curb extension areas, as shown in Exhibit 1510-20. Take into account motorist and pedestrian visibility and Design Clear Zone guidelines (see Chapter 1600).

1510.11 Raised Medians/Traffic Islands

Wide multilane streets are often difficult for pedestrians to cross, particularly when there are insufficient gaps in vehicular traffic because of heavy volumes. Consider raised medians and traffic islands with a pedestrian refuge area (see Exhibit 1510-21) on roadways with the following conditions:

Two-way arterial with intermediate to high speeds (35 mph or greater), moderate to high average daily traffic (ADT), and high pedestrian volumes.

Significant pedestrian collision history.

Near a school or other community center.

Crossing distance exceeds 30 feet.

Complex or irregularly shaped intersections.

A traffic island used for channelized right-turn slip lanes can provide a pedestrian refuge, but the slip lane may promote faster turning speeds. Minimize the turning radius of the slip lane to keep speeds as low as feasible. To reduce conflicts, keep the slip lane as narrow as practicable and design a crosswalk alignment that is at a right angle to the face of curb. (See Chapters 1310 for turn lanes, 1360 for interchange ramps, and 1320 for pedestrian accommodations in roundabouts.)

The pedestrian access route through a raised median or traffic island can be either raised with curb ramps or a cut-through type (see Exhibit 1510-21). Curb ramps in medians and islands can add difficulty to the crossing for some users. The curbed edges of cut-throughs can be useful cues to the visually impaired in determining the direction of a crossing, especially on an angled route through a median or island.

(1) Accessibility Criteria for Raised Medians and Traffic Islands

There are many design considerations when deciding whether to ramp up to the median or island grade or create a cut-through median or island matching the roadway grade. These considerations may include profile grade and cross slope of the road, drainage patterns, and the length or width of the median or island.

The following accessibility criteria apply:

Each raised median or traffic island shall contain a pedestrian access route connecting to each crosswalk (see 1510.07).

Provide a passing space at least 5 feet wide for a distance of at least 5 feet for each pedestrian access route in a raised median or on a traffic island (see Exhibit 1510-21).

Note: It is recommended that cut-throughs be designed to have a minimum width of 5 feet to ensure a passing space is provided.

Medians and pedestrian refuge islands shall be 6 feet minimum in length in the direction of pedestrian travel.

Detectable warning surfaces are to be separated by 2 feet minimum length in the direction of pedestrian travel.

Detectable warning surfaces are located at each curb ramp or roadway entrance of a pedestrian access route through a raised median or traffic island. The detectable warning surface shall be located at the back of the curb (see Exhibit 1510-21).

When the pedestrian access route of a shared-use path goes through a raised median or traffic island, the width shall be the same as the width of the shared-use path (see Chapter 1515).

Island Cut-Through

Island Cut-Through

Detectable warning

surface (Typ.)

5' - 0"

Min.

Curb ramp (Typ.)

Median Island Cut-Through (full width shown)

(See 1510.11(1) for minimum accessibility criteria.)

Raised Traffic Island With Curb Ramps

See the Standard Plans for details.

Raised Islands With Curb Ramps and Pedestrian Cut-Throughs

Exhibit 1510-21

1510.12 Pedestrian Push Buttons at Signals

When designing pedestrian signals, consider the needs of all pedestrians, including older pedestrians and pedestrians with disabilities who might walk at a significantly slower pace than the average pedestrian. Determine whether there are pedestrian generators in the project vicinity that might attract older people and pedestrians with disabilities, and adjust signal timing accordingly. Include accessible pedestrian pushbuttons and countdown pedestrian displays at all locations. Consult with region and city maintenance personnel regarding maintenance requirements for these devices.

Locate pedestrian push buttons in accordance with the most current edition of the

Public Rights-of-Way Accessibility Guidelines (PROWAG) and the MUTCD.

Clearly identify which crossing is controlled by the push button.

Provide a level clear space (maximum 2% running and cross slopes, 4 feet minimum length by 2 feet 6 inches minimum width) within reach range at each push button for wheelchair users. The level clear space must be connected to the crosswalk it serves by a pedestrian access route.

Mount push button at an approximate height of 3 feet 6 inches (but no greater than 3 feet 10 inches) above, and a maximum horizontal distance of 2 feet from the level clear space surface.

(1) Accessible Pedestrian Signals (APS)

At all locations where pedestrian signals are newly installed, replaced, or significantly modified, the installation of accessible pedestrian signals (APS) and countdown pedestrian displays is required. (Note: Simply moving existing pedestrian push buttons to satellite poles to improve accessibility is not by itself considered a significant modification of the pedestrian signal.) When APS and countdown pedestrian display improvements are made, they shall be made for all locations associated with the system being improved. APS includes audible and vibrotactile indications of the WALK interval. Installation of these devices may require improvements to existing sidewalks and curb ramps to ensure ADA compliance.

Refer to the MUTCD and the most current edition of the PROWAG for design requirements. Also, consult with HQ Traffic Operations, the HQ Design Office, and region and city maintenance personnel for current equipment specifications and additional design and maintenance requirements.

1510.13 At-Grade Railroad Crossings

The design of pedestrian facilities across railroad tracks (see Exhibit 1510-22) often presents challenges due to the conflicting needs of pedestrians and trains. In particular, the flangeway gap for trains to traverse a crossing surface may create a significant obstacle for a person who uses a wheelchair, crutches, or walking aids for mobility. Whenever practicable, make crossings perpendicular to the tracks in order to minimize potential problems related to flangeway gaps. Crossing surfaces may be constructed of timber planking, rubberized materials, or concrete. Concrete materials generally provide the smoothest and most durable crossing surfaces. When detectable warning surfaces are used at railroad crossings, place them according to the MUTCD stop line placement criteria.

Pedestrian Railroad Crossings

Exhibit 1510-22

There are a number of railroad crossing warning devices (see Exhibit 1510-23) intended specifically for pedestrian facilities (see the MUTCD). When selecting warning devices, take into account such factors as train and pedestrian volumes, train speeds, available sight distance, number of tracks, and other site-specific characteristics. Coordinate with the HQ Design Office Railroad Liaison early in the design process so that all relevant factors are considered and an agreement may be reached regarding the design of warning devices and crossing surfaces.

Pedestrian Railroad Warning Device

Exhibit 1510-23

Except for crossings located within the limits of first-class cities,* the Washington Utilities and Transportation Commission (WUTC) approves proposals for any new railroad at-grade crossings or changes to warning devices or geometry at existing crossings. Additionally, any project that requires the railroad to perform work such as installation of warning devices or crossing surfaces must obtain a railroad construction and maintenance agreement. Contact the HQ Design Office Railroad Liaison to coordinate with both WUTC and the railroad company.

*RCW 35.22.010: A first class city is a city with a population of ten thousand or more at the time of its organization or reorganization that has a charter adopted under Article XI, section 10, of the state Constitution.

There are few first-class cities in the state of Washington. Consult with the HQ Design Office Railroad Liaison.

1510.14 Pedestrian Grade Separations (Structures)

On the approach to a bridge that has a raised sidewalk, provide a ramp that transitions to the sidewalk from the paved shoulder. A ramp that transitions from a paved shoulder to a sidewalk on a bridge is to have a slope of 5% maximum and be constructed of asphalt or cement concrete. In addition to aiding pedestrian access, the ramp also serves as a roadside safety feature to mitigate the raised, blunt end of the concrete sidewalk. If a pedestrian circulation path (such as a raised sidewalk or shared-use path) is located near the bridge, consider eliminating the gap between the bridge sidewalk and the pedestrian circulation path by extending the bridge sidewalk to match into the nearby pedestrian circulation path.

At underpasses where pedestrians are allowed, it is desirable to provide sidewalks and to maintain the full shoulder width. When bridge columns are placed on either side of the roadway, it is preferred to place the walkway between the roadway and the columns for pedestrian visibility and security. Provide adequate illumination and drainage for pedestrian safety and comfort.

In cases where there is a pedestrian collision history, and the roadway cannot

be redesigned to accommodate pedestrians at grade, planners should consider providing a grade-separated pedestrian structure (see Exhibits 1510-24 and 1510-25). When considering a pedestrian grade-separation structure, determine whether the conditions that require the crossing are permanent. If there is likelihood that pedestrians will not use a grade separation, consider less-costly solutions.

Locate the grade-separated crossing where pedestrians are most likely to cross the roadway. A crossing might not be used if the pedestrian is required to deviate significantly from a more direct route.

It is sometimes necessary to install fencing or other physical barriers to channel the pedestrians to the structure and reduce the possibility of undesired at-grade crossings. Note: The HQ Bridge and Structures Office is responsible for the design of pedestrian structures.

Consider a grade-separated crossing where:

There is moderate-to-high pedestrian demand to cross a freeway or expressway.

There are large numbers of young children, particularly on school routes, who regularly cross high-speed or high-volume roadways.

The traffic conflicts that would be encountered by pedestrians are considered unacceptable (such as on wide streets with high pedestrian volumes combined with high-speed traffic).

There are documented collisions or close calls involving pedestrians and vehicles.

One or more of the conditions stated above exists in conjunction with a well-defined pedestrian origin and destination (such as a residential neighborhood across a busy street from a school).

(1)Pedestrian Bridges

Pedestrian grade-separation bridges (see Exhibit 1510-24) are more effective when the roadway is below the natural ground line, as in a cut section. Elevated grade separations in cut sections, where pedestrians climb stairs or use long approach ramps, tend to be underused. Pedestrian bridges need adequate right of way to accommodate accessible ramp approaches leading up to and off of the structure. The bridge structure must comply with ADA requirements and meet the accessibility criteria for either a pedestrian circulation path (if the grade is 5% or less) or an access ramp (if the grade is greater than 5% but less than or equal to 8.3%), and must include a pedestrian access route. (See 1510.06 and 1510.07 for pedestrian circulation path and pedestrian access route accessibility criteria; see 1510.15(2) for access ramp accessibility criteria.)

For the minimum vertical clearance from the bottom of the pedestrian structure to

the roadway beneath, see Chapter 720. The height of the structure can affect the length of the pedestrian ramp approaches to the structure. When access ramps are not feasible, provide both elevators and stairways.

Provide railings on pedestrian bridges. Protective screening is sometimes desirable to deter pedestrians from throwing objects from an overhead pedestrian structure (see Chapter 720).

The minimum clear width for pedestrian bridges is 8 feet. Consider a clear width of 14 feet where a pedestrian bridge is enclosed or shared with bicycles or equestrians.

Pedestrian Bridges

Exhibit 1510-24

(2)Pedestrian Tunnels

Tunnels are an effective method of providing crossings for roadways located in embankment sections. Well-designed tunnels can be a desirable crossing for pedestrians. When feasible, design the tunnel with a nearly level profile to provide an unobstructed line of sight from portal to portal (see Exhibit 1510-25). People may be reluctant to enter a tunnel with a depressed profile because they are unable to see whether the tunnel is occupied. Police officers also have difficulty patrolling depressed profile tunnels.

Provide vandal-resistant daytime and nighttime illumination within the pedestrian tunnel. Installing gloss-finished tile walls and ceilings can enhance light levels within the tunnel. The minimum overhead clearance for a pedestrian tunnel is 10 feet. The minimum width for a pedestrian tunnel is 12 feet. Consider a tunnel width between 14 and 18 feet depending on usage and the length of the tunnel.

Pedestrian Tunnel

Exhibit 1510-25

Pedestrian tunnels need adequate right of way to accommodate accessible approaches leading to the tunnel structure. The tunnel structure must comply with ADA requirements and meet the accessibility criteria for either a pedestrian circulation path (if the grade is less than or equal to 5%) or an access ramp (if the grade is greater than 5% and less than or equal to 8.3%), and must include a pedestrian access route. (See 1510.06 and 1510.07 for pedestrian circulation path and pedestrian access route accessibility criteria; see 1510.15(2) for access ramp accessibility criteria.)

1510.15 Other Pedestrian Facilities

(1)Transit Stops and School Bus Stops

The location of transit stops is an important element in providing appropriate pedestrian facilities. (Coordinate with the local transit provider.) Newly constructed transit stops must conform to ADA requirements (see Chapter 1430). Design newly constructed transit stops so they are accessible from the sidewalk or paved shoulder. A transit stop on one side of a street usually has a counterpart on the opposite side because transit routes normally function in both directions on the same roadway. Provide adequate crossing facilities for pedestrians.

When locating a transit stop, consider transit ridership and land use demand for the stop. Also, take into account compatibility with the following roadway/traffic characteristics:

ADT

Traffic speed

Crossing distance

Collision history

Sight distance

Connectivity to a pedestrian access route

Traffic generator density

If any of these suggests an undesirable location for a pedestrian crossing, consider a controlled crossing or another location for the transit stop.

When analyzing a transit stop location with high pedestrian collision rates, take into account the presence of nearby transit stops and opportunities for pedestrians to reasonably safely cross the street. At-grade midblock pedestrian crossings may be

effective at transit stop locations on roadways with lower vehicular volumes. Pedestrian grade separations are appropriate at midblock locations when vehicular traffic volumes prohibit pedestrian crossings at grade. (See Exhibit 1510-28 for recommendations for marked crosswalks at unsignalized intersections.)

School bus stops are typically adjacent to sidewalks in urban areas and along shoulders in rural areas. Determine the number of children using the stop and provide a waiting area that allows the children to wait for the bus. Coordinate with the local school district. Because of their smaller size, children might be difficult for motorists to see at crossings or stops. Determine whether utility poles, vegetation, and other roadside features interfere with the motorist’s ability to see the children. When necessary, remove or relocate the obstructions or move the bus stop. Parked vehicles can also block visibility, and parking prohibitions might be advisable near the bus stop. Coordinate transit and school bus stop locations with the region Traffic Office.

(2) Access Ramps Serving Transit Stops, Park & Ride Lots, Rest Areas, Buildings, and Other Facilities

An access ramp (see Exhibit 1510-26) provides an accessible pedestrian route from

a pedestrian circulation path to a facility such as a transit stop, park & ride lot, rest area, pedestrian overcrossing/undercrossing structure, or building. When the running slope is 5% or less, it can be designed as a pedestrian circulation path that includes a pedestrian access route. When the running slope is greater than 5% to a maximum of 8.3%, it must be designed as an access ramp. (See 1510.06 and 1510.07 for pedestrian circulation path and pedestrian access route accessibility criteria; see 1510.15(2)(a) for access ramp accessibility criteria.)

(a)Accessibility Criteria for Access Ramps

Access ramps are comprised of one or more ramp segments interconnected by level landings. Unless superseded by the following specific accessibility requirements for access ramps, the accessibility requirements for pedestrian access routes also apply:

Ramp segments shall have a maximum running slope of 8.3%.

The cross slope of ramp segments shall be 2% maximum.

The minimum clear width of ramps is 4 feet; however, it is desirable to match the width of the connecting pedestrian facility.

The rise for any ramp segment shall be 30 inches maximum.

A level landing (2% maximum perpendicular and parallel slopes) shall be provided at the top and bottom of each access ramp segment.

An access ramp landing’s clear width shall be at least as wide as the widest ramp segment leading to the landing.